Differential-transmission mechanism.



Patented J an. 8, 1918.

n.` N. BICKLEY, DIFFERENTIAL TRANSMISSION VMECHANISNI. `APPLICATION FILED MKII. I. 19H- l'I I Q l MN NM N ik. mM/v mv GTI NN QN Q mm .Q *N Q mw. w am mm nu R w Ra N v I I Q m N RALPH N. nIcxLEY, orV MINNEAPOLIS, MINNESOTA.

To all whom t may concern:

Be it known that I, RALPH citizen of the United States, residing at Mlnneapolis, in the county of Hennepin and State of Minnesota, have invented certain new and useful Improvements in Differential-Transmission Mechanism; and I .fdo hereby declare the following to be a full, clear, and exact descriptionl of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention has for its object to provide an improved differential transmission for motor-propelled vehicles.` The invention, however, is more lparticularly adapted for use in connection with heavy slow moving motor propelled vehicles that are generally designated as tractors.

The object of the invention is to combine with the dierential gear mechanism, clutch N. 'Brennan a devices, whereby either one of two laterally spaced traction wheels may be positively driven while the other is idle, tov thereby cause the tractor to be positively and abruptly turned in either direction, at will.

My invention consists in applying clutches in the connections between the two and the corresponding differential driven shafts or rotary members of the differential gear. Such application of the clutches, in connection with the customary beveled gear differential, for example, would bel futile and impracticable, because, when the clutch on one side is thrown out, the released differentially driven members would simply spin and there would be no resistance against which to drive the wheel on the other side.

I haveyhowever, found that by applying the clutches, as above stated, in connection with what may be designated as a self-locking differential, the desirable results above indicated will be attained and it is possible to positively drive either both traction wheels, differentially through the transmission mechanism, or to positively drive either one of the two traction wheels through the said differential gear while the other traction wheel is idle and no driving force applied thereto.

DIFFERENTIAL-Transmission mncnansm. l

specifi-mi@ waaraan f patents@ Ap'pnemda mediteren 11,191.7. '.srmnewmae.

wheels v Ais secured -to the side bars -By a self-locking'diferential, is meant a differential which will dierentially drive two traction wheels in turning corners, or in devlating from straight line travel, but which will not cause one of the traction wheels to spin ahead of the other, even if such wheel vbe entirely lifted fromv the ground. .Y A self-locking dierential gear of this character is in extensive commercial use and 1s known to the trade as the.M & S dierential, the same being manufac- .tu'red by the M &' S Company, of Detroit, `Michigan; and in the accompanying drawings I have illustrated my invention as applied in connection with a worm or spiral gear differential transmission of the said |M & S type.

In the accompanying drawings which illustrate .the invention, like characters indicate' like parts throughout the several views. 4

Referring to the drawings;

Figure 1 is a horizontal section with some parts broken away, illustrating one of the Ways of applying my invention;

Fig. 2 is a vertical section on the line 2-2 of Fig. 1; and

Fig. 3`is a vertical section on the line 3-3 of Fig. 1.

Of the parts of the tractor illustrated, the numeral 4 indicates the laterally spaced traction wheels having internal gears 5; the numerals 6 and 7 indicate side and cross bars of the truck frame; the numeral 8 `indicates, as an entirety, dii'erential gear housing,

6, and at its front intermediate portion is connected to the cross bar 7 the numeral 9 indicates axially alined shafts journaled in suitable bearings in the housing 8 and capable of independent rotation; and the numeral 10 indicates pinions secured to the outer ends of the shafts 9 and meshing with the internal gears 5 of the traction wheels 4. The numeral 11 indicates the engine-driven shaft journaled in a suitable bearing in the gear housing and the rear axle'and which, at its ends,`

Jan.

gear 13. This bevel gear 13 is the master 1o f housing 8, as shown, by means of roller bearments 14 and 15' have hubs journaled in the ings 17. Journaled in the hubs of the said elements 14 and 15 and loosely journaled on the inner ends of the respective shafts 9 are these spiral or worm sleeves 18, which at their inner ends are provided with Worm secured halfclutches 19 mesh with smaller 21 that have shafts 22 ber 16 of the master 20. The worm gears worm or spiral gears wheel (see particularly Fig. 2). These spiralV gears 21 are in the` commercial form of the M& S differential, arranged inl multiple, or in sets, as shown in Fig. 2,. and the transversely opposite spiral gears 21 mesh with an intermediate spiral gear 23, the shaft 24 of which is radially disposed in respect to the axis of the shafts 9.

The differential action produced through gears in turning corners with both wheels on the ground is substantially the same as that in an ordinary differential, but the said worm gears are Set at such angle that instantly and automatically, the driving force will be concentrated on the wheel which is free or offers relatively little resistance, will not be causedto spin ahead of the wheel that is firmly set upon the ground, or that has good traction with the ground. The said differential gear is, therefore, selflocking against spinning movements of a loose or free wheel ahead of the other.

Inthis arrangement, it will be remembered that the sleeve-like hubs of the Worm gears 19 are loose on the respective shafts 9. They are, however, adapted to be-coupled to the said respective Ashafts 9 by means of sliding half clutches 25 that coperate with the respective half clutches 20. Th clutches 25 are keyed to rotate with the respective shafts 9, but free to slide thereon, and I moreover, are preferably subject to coiled springs 26 that tend to keep the Said coperating half clutches engaged. These coiled springs 26, as shown, surround the respective shafts 9 and re-act against collars 27 thereon. The half clutches 20 and 25 are shown as of the positive ntermeshing t but in some cases, they might be friction clutches.

For moving the half clutches 25 into released positions, I 'have shown shipper 1efor example,

or spiral gears 19, and at their outer ends areprovided with rigidly I journaled in the mem-4 ese half may be-operated from a distant point, either fby foot or by hand power.

bvlously, when both of \the clutches are.

engaged, the two traction wheels will be differentially driven, but neither thereof vcan be caused to slip or spring ahead of the other. When the clutch at the right is disengaged,

asA shownA in Fig. 1, it 1s evident that all of the power will be transmitto the left hand traction wheel thereby causlng the tractor to turn toward the right. Obviously, also, in like manner, the tractor may be positively caused to turn toward the left by releasing the left hand the .right hand clutch is in action. This gives a very positive means for causing a tractor to positively turn short corners, or to turn completely around within4 smalls ace, and to do this, also, regardless of cond1tion pf the soil. The application of the clutches 1n combination wlth va self-locking differential, is believed to be new and Ais known to be hlghly important, especially-in connec-` tion with tractors.

In the drawings, the clutches are shown as applled to shafts that carry pinions for di-l rect engagement with gears on the Atraction wheels, but'in other arrangements, clearly within the scope of the invention, the said divided shaft might nectedv to the traction wheels through other or entirelydifferent transmission mechamsm.

What I claim is:

1. The combination `with the traction wheels of a vehicle, of a transmission mechanism connected to the 'said two traction wheels and comprising a locking differential gear, andl clutches applied between said differential gear and thesaid traction wheels and operative, at will, to connect said differential gear, independently to either traction wheel, or simultaneously to both traction wheels.

2. The combination with the traction wheels of'a vehicle, of a transmission mechanism connectedto the said 'two traction wheels and comprising a self-locking differential gear, and clutches applied between said differential gear and the Said traction wheels and operative, at will, to connect said differential gear, independently to either traction Wheel, or simultaneously lto bothv traction wheels, the said clutches having spring devices normally holding the same operative and havin connections for independently releasing the same.

3. e combination wheels of a vehicle, of 'a transmission mechaclutch, while be a counter shaft conwith the traction nism comprising devices connectin g said aline each side of but slidable on sald two i 1,25,sss

self-locking worm gear diierential, two alined shafts,

transmission d Shafts, one half clutches, Said diierenhalf clutches earned alined shafts ment ferentially 11i testimony whereof I aix Witnesses:

CLARA DEMABEST, BERNICE G. WHEELER.

with the coperating first noted dfdriven half clutches..

my signature in presence of two witnesses.

` RALPH N. BICKLEY. 

